Clinical trial Recruiting at 1 site Phase 2 Interventional Ages Any age to 21

End-of-chemotherapy B7-H3 CAR T cells for high-risk pediatric osteosarcoma

Official title: A Phase II Study Evaluating Efficacy of B7-H3-CAR T Cells Administered at the End of Upfront Map Chemotherapy in Patients With Newly Diagnosed High-Risk Osteosarcoma

Run by St. Jude Children's Research Hospital · NCT07428993 · Data updated 2026-11-12

This study tests whether giving a patient’s own B7-H3 CAR T cells after standard chemotherapy can help treat newly diagnosed high-risk osteosarcoma in children.

Quick facts

PhasePhase 2
Study typeInterventional
AgesAny age to 21 Years
SexAll
Enrollment41 (estimated)
SponsorSt. Jude Children's Research Hospital
Academic / other
Drugs / interventionschemotherapy, methotrexate, CAR T
Locations1 site (Memphis, Tennessee)
StatusRecruiting
StartedAugust 21, 2026
Main results expectedDecember 2034
Study endsDecember 2035
Registry record updatedNovember 3, 2026
Trial IDNCT07428993 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are children or adolescents with newly diagnosed high-risk metastatic osteosarcoma who have completed standard chemotherapy and meet inclusion criteria including adequate performance status and no progressive disease.

Probably not a fit

Patients with rapid disease progression, insufficient car T product availability, or inability to tolerate lymphodepletion may not benefit.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This phase 2 trial enrolls pediatric patients with newly diagnosed high-risk metastatic osteosarcoma who have completed standard chemotherapy. After apheresis and local control surgery, eligible participants may receive lymphodepletion followed by autologous SJCARB7H3-41BBL CAR T cell infusion either after consolidation chemotherapy or after pulmonary metastasectomy, depending on regimen clearance. Participants are then followed for disease evaluations for up to two years. The study measures 1-year relapse-free survival and overall survival, while assessing feasibility and safety of the CAR T cell therapy delivered at the end of standard therapy.

Why it matters

Potential benefit: If successful, the approach could improve disease control and survival for children with high-risk osteosarcoma when added after standard treatment.

How similar studies have gone: Previous studies in solid tumors and osteosarcoma have explored CAR T cells with varying results; this study applies a novel B7-H3 CAR approach in the consolidative setting.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Participant and/or legally authorized representative has signed the Informed Consent Form for this study
2. Prior cancer therapy:

   * Regimen A only: Completed all planned cycles of consolidation therapy between 14-28 days prior.
   * Regimen B only: has completed all planned cycles of consolidation chemotherapy at least 14 days prior and if clinically indicated, participant has undergone pulmonary metastasectomy. They must have recovered from any surgical complications with no ongoing sequelae of category 2 or higher by the Clavien-Dindo classification system and less than 6 weeks must have passed from time of pulmonary metastasectomy.
3. No evidence of progressive disease since enrolled on study
4. Lansky performance status score of ≥ 50 for participants \<16 years of age or Karnofsky score ≥ 50 for participants ≥ 16 years. Participants who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for purposes of assessing performance status
5. Adequate organ function as indicated by:

   * Renal: Serum creatinine ≤ 1.5 X the upper limit of normal (ULN) based on enrollment eligibility table.
   * Hepatic: Total bilirubin ≤ 3 times ULN for age OR conjugated bilirubin ≤ 2 mg/dL AND ALT (SGPT) ≤ 5 times ULN
   * Cardiac: Shortening fraction ≥ 28% OR ejection fraction ≥ 50% as measured by echocardiogram
   * Respiratory: Oxygen saturation ≥ 90% on room air without supplemental oxygen or mechanical ventilation
6. Laboratory values meet the following criteria:

   * Absolute Neutrophil Count (ANC) ≥ 750 cells/uL
   * Platelet Count of ≥ 75,000 (can be transfused)
   * Hemoglobin ≥ 7 g/dL (can be transfused)
7. Participant is ≥ 7 days from receiving supra-physiologic dosing of systemic (IV or PO) corticosteroids. Glucocorticosteroid physiologic replacement therapy for management of adrenal insufficiency is allowed.
8. Participant and/or legally authorized representative has signed the Informed Consent Form for the treatment phase of this study.

Exclusion Criteria:

1. Major surgical adverse event related to the primary tumor local control defined as Clavien-Dindo category 3 requiring ongoing wound care.
2. Evidence of clinically significant encephalopathy/new focal neurologic deficits.
3. Presence of active severe infection, defined as:

   * positive blood culture within 48 hours of enrollment, OR
   * fever above 38.2° C, AND clinical signs of infection within 48 hours of enrollment
4. Participant has received prior disease-directed therapy other than 1st line therapy with methotrexate, an anthracycline, and a platinum and local control surgery

   • Regimen B only - okay to have undergone initial pulmonary metastasectomy
5. Pregnant or breastfeeding
6. Presence of any condition that, in the opinion of the investigator, would prohibit the participant from undergoing treatment under this protocol

Where it's running

  • St. Jude Children's Research Hospital
    Memphis, Tennessee, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.